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    Re: Knot strength
    From: Peter Smith
    Date: 1999 Apr 08, 11:28 AM

    Rodney Myrvaagnes [mailto:rodneym{at}ibm.net] said:
    > Except that the extra tucks don't weaken the part of the
    > line they tuck into any more than the first three weaken
    > their part of the rope.
    ...
    
    Sometime in the last year or so, Practical Sailor addressed failures in
    Nylon line. I'm on the road this week and can't check back -- it was either
    a sidebar to a test of various lines, or a review of hurricane precautions.
    In any case, they mentioned that many failures of Nylon anchor or dock lines
    were not due to chafe, but to heat damage from repeated shock loads. It
    appears that when Nylon load up, the fibers rub and heat up, and if the
    cycling is violent enough, the heat gets high enough to permanently weaken
    the line. The damage is cumulative and the line eventually fails.
    
    Could it be that the more tucks you have in a splice, the more friction
    is created? Or more precisely, the more chance of a tight-radius bend
    in one of the strands, leading to a point failure? Thus, the more tucks,
    the greater chance that you've introduced a weakpoint.
    
    I agree with Rodney -- I'd like to see some detailed data on failures.
    
     -- Peter (who was always taught to take four tucks in synthetic line,
               plus two more to taper off the strands)
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